If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

My owners manual indicates you can run anything between 87 and 91 octane fuel, but premium is recommended for optimum performance.

I suspect I will likely run either 89 or 91 octane since I can actually find those two without ethanol added to it.

What are ya'll using and do you notice any difference in performance and fuel economy using the various octane ratings?

Our 08 SM5 runs best on 93. Fuel mileage is consistently in the mid 30's. BRP has told us that the Spyder's ECM can detect ignition detonation that occurs with a lower octane fuel, and retard timing accordingly to control it. With that comes a loss of performance, and fuel mileage. Some say that they don't notice a difference with a lower octane rating, and I'm sure they don't. Some of us do feel the difference, and many have reported better mileage as well. Altitude, riding style, terrain, weather, and riding environment all play into the equation as well......

We used to be able to get 93 octane here until the tree huggers forced ethanol on us. Now it is 87, 89, or 91 octane. A few and that is very few gas stations sell real gas without ethanol, but most of those are 91 octane only.

I've tried all three...no real difference...at least not enough to justify 20 cents or more per gallon.

Then someone pointed out that it's only like a dollar difference per tank load...and that's a good point....however, I really don't see any difference and that is the overriding issue for me...so, 87 I go...

Bone Crusher
If you work to make money, you'll never be happy, as there's never enough money...if you work to take good care of people, the money will always be there....Sean O'Connell, 1999

With one comment. They says premium doesn't help unless you own a premium vehicle with a high output motor. While the Rotax isn't low compression low output like some certain bikes, I don't think it's really high output for it's size/configuration either. I think BRP's recommendation of 87 octane means it shouldn't need to do any timing changes to prevent detonation at that octane level baring unusual circumstances (poor air conditions, pressure, very high ambient temps etc.)

Octane

Just completed a three day run on the Blue Ridge and ran regular 87 all the time. With but 3100 miles on the RT, we turned in a steady 33mpg. Speaking with our local Spyder guru, he said try running all three grades over a period of time to see which works best. Made some comment that no two engine/ ECM combinations are alike and we might find that we get better performance out of premium, or just plain old regular. No more than the cost difference is right now, the experiment is on. Oh, he did mention a Power Commander mod. I dunno 'bout that.

My experience: Tried 87 octane for the first 3 tanks this year on RTS--the bike did not seem to run as "peppy," also noticed less fuel mileage per gallon. I'm back to 91 octane untill I can't afford it any more. Also drive a Subaru Tribca (V6 and recommended 90+octane)--exactly the same results. Back to premium.

My experience: Tried 87 octane for the first 3 tanks this year on RTS--the bike did not seem to run as "peppy," also noticed less fuel mileage per gallon. I'm back to 91 octane untill I can't afford it any more. Also drive a Subaru Tribca (V6 and recommended 90+octane)--exactly the same results. Back to premium.

Careful, there is a break-in period regardless of what fuel you are running and your mileage will get better over the first 1000 miles...

Bone Crusher
If you work to make money, you'll never be happy, as there's never enough money...if you work to take good care of people, the money will always be there....Sean O'Connell, 1999

I had always stayed true to only using premium if the engine called for it because of compression requirements. I read here that the timing changed to stop knock. I tried a tank of premium, mid- grade & regular. I didn't notice a difference between mid-grade (89) and premium (91), but they both performed better than regular (87). No milage difference between any of them for me. It took about 100 km to see the difference. Premium is 60 cents more a gallon here in Canada, mid-grade is 40 cents more. I use regular if I am just cruising on the highway but go to 89 if I am looking at any performance riding (my usual fill-ups). I don't bother with 91 Octane.

Bone crusher--mileage did seem to improve after the initial 3000 miles or so. I started in the high 20's (27) and most tanks average (31) now. I am not an agressive driver, drive with the windscreen at its lowest point most of the time, and keep the revs mostly around 4500.

Yup, definitely saw an improvement in mileage per tank as the miles were put on the engine. I pretty much stick to 89 and every so often 91 octane now. I do feel at least "the perception" of better performance with the 89-91 octane. I cannot really confirm improved MPG, but the machine does seem to run better with the better grades of fuel. I do not put in any additives either.

Yup, definitely saw an improvement in mileage per tank as the miles were put on the engine. I pretty much stick to 89 and every so often 91 octane now. I do feel at least "the perception" of better performance with the 89-91 octane. I cannot really confirm improved MPG, but the machine does seem to run better with the better grades of fuel. I do not put in any additives either.

Yeah...I think most sources will say that it's a psychological effect more than a true mechanical one...

I use 87 and my bike is fine with it...when running 93, I really didn't see a change, except for an additional 20+ cents/gallon.

I do have numbers on my old BMW...I get about 2mpg higher with 89, even though the old '92 only 'needed' 87...funny thing is that with 93, it runs the same as with the 87....odd...I guess with age, it gets a little pickier. Who knows...

Bone Crusher
If you work to make money, you'll never be happy, as there's never enough money...if you work to take good care of people, the money will always be there....Sean O'Connell, 1999